Initial observation of grain boundary solute segregation in a zirconium alloy (ZIRLO) by three-dimensional atom probe

Three-dimensional atom probe has been used to measure solute segregation to grain boundaries in ZIRLO, a Zr–Nb–Sn–O–Fe alloy. It was found that Fe segregates strongly, along with a substantial amount of Nb. No statistically significant segregation of Sn, O, C or N was detected. The results are discussed in the context of the likely effect of heat treatment and irradiation on solute distribution in Zr alloys.